There are 2 places that titles can be that may be showing up on any given page
1. Within the individual article
2. Within the menu item
First, lets talk about double title problems
First you should go into the article and see if there is a title in the body of the article
If it is in the body simply delete it then save and close.
Refresh your front end view page and verify that the title has been deleted
If that did not fix the title problem it check the article setttings. This step applies to setting it to show or not show as your needs dictate.
Go to the "Options" tab and click the dropdown next to "Show Title" and select the option that meets your needs.
-Use Global means use the settings as they are
Refresh your front end view page and verify that the title has been changed as you wished.
Lastly you can change the title settings within the menu item
Go to the individual menu item and you will check the settings in the "Options" tab and the "Page Display" tab
For the "Options" tab follow the same steps as above for the options tab in the article settings.
For the "Page Display" tab simply add or remove information in these fields as needed.